Playing in front of Japanese fans for the first time as a Grand Slam winner was a special moment, newly crowned U.S. Open champion Naomi Osaka said Wednesday.

Less than two weeks after becoming the first Japanese major winner at Flushing Meadows, Osaka cruised through her first match at the Pan Pacific Open against Slovakia's Dominika Cibulkova.

While happy with her performance in the 6-2, 6-1 victory at Arena Tachikawa Tachihi, the 2016 Pan Pacific finalist said her overwhelming feeling was gratitude at her warm reception from Japanese fans.

"My first match (since the U.S. Open) in Tokyo felt really special," Osaka said. "I didn't really feel pressure, I felt more excitement, because I knew that a lot of people were watching this match. I felt really grateful."

The quick turnaround between the U.S. Open and the current tournament had given her little time to think about the significance of her historic victory in New York, she said.

"I think I'm glad that I'm playing in Tokyo. I'm already at this tournament, so I'm not really thinking that I won the U.S. Open," Osaka said. "I'm not really sure what will happen when things calm down."

The world No. 7, who served 10 aces and hit a slew of unreturnable winners against Cibulkova, said she had yet to hit top form ahead of her quarterfinal meeting with Barbora Strycova of the Czech Republic.

"As a whole I can say I played maybe, like, 80 percent. For me I never know the limit of what level I can go to," said Osaka, who received an opening-round bye as the third seed.

The 20-year-old, who was born in Japan and raised in New York by her Japanese mother and Haitian father, said she hoped to be able to spend some free time after the tournament in one of Tokyo's youth fashion hubs.

"When I was in New York, I really wanted to go to Harajuku, and ride the jet coaster in Tokyo. But when I came here, I didn't have time to do anything like that, so that was a little bit sad," she said. "But...right now, I don't know, I'll see what happens after the tournament."

She also reiterated plans to relax her diet and indulge in some Japanese soul food -- "katsu-don" deep fried pork cutlets on rice.

"Everyone knows that I really want to eat katsu-don, so after the tournament, when I'm not on a strict diet, maybe I'll try that," she said.